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TI-2024-34402 Aliases CVE-2024-51481

Nix allows macOS sandbox escape via built-in builders

Priority LOW 6CWE-693Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
Passive
Attack complexity
High
Attack requirements
Present
Impact type
Security bypass
Confidentiality · integrity · availability
Low · Low · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-693.

Summary

Nix is a package manager for Linux and other Unix systems. On macOS, built-in builders (such as `builtin:fetchurl`, exposed to users with `import <nix/fetchurl.nix>`) were not executed in the macOS sandbox. Thus, these builders (which are running under the `nixbld*` users) had read access to world-readable paths and write access to world-writable paths outside of the sandbox. This issue is fixed in 2.18.9, 2.19.7, 2.20.9, 2.21.5, 2.22.4, 2.23.4, and 2.24.10. Note that sandboxing is not enabled by default on macOS. The Nix sandbox is not primarily intended as a security mechanism, but as an aid to improve reproducibility and purity of Nix builds. However, sandboxing *can* mitigate the impact of other security issues by limiting what parts of the host system a build has access to.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00171 6th percentileScored 2026-11-07
Fix Fixed nix (NixOS): 2.18.9, 2.20.9, 2.21.5 +3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
NixOSnixbefore 2.18.9; >= 2.19.0, < 2.19.7, 2.20.9, 2.21.5, 2.22.4, 2.23.4, 2.24.10; 2.20.0 to before 2.20.9; 2.21.0 to before 2.21.5; 2.22.0 to before 2.22.4; 2.23.0 to before 2.23.4; 2.24.0 to before 2.24.102.18.9, 2.20.9, 2.21.5, 2.22.4, 2.23.4, 2.24.10Patch availableCNA
  • nix VendorNixOS Affected before 2.18.9; >= 2.19.0, < 2.19.7, 2.20.9, 2.21.5, 2.22.4, 2.23.4, 2.24.10; 2.20.0 to before 2.20.9; 2.21.0 to before 2.21.5; 2.22.0 to before 2.22.4; 2.23.0 to before 2.23.4; 2.24.0 to before 2.24.10 Fixed in 2.18.9, 2.20.9, 2.21.5, 2.22.4, 2.23.4, 2.24.10 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:nixos:nix:*:*:*:*:*:*:*:*——NixOS
  • cpe:2.3:a:nixos:nix:*:*:*:*:*:*:*:* Versions — — ·NixOS

Remediation

  • Fix · CNA nix (NixOS) Fixed in 2.18.9, 2.20.9, 2.21.5, 2.22.4, 2.23.4, 2.24.10

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-51481

References

Other 2

  • TI-2026-23989 crypto: algif_aead - Revert to operating out-of-place KEVCVSS 3.1HIGH 7.8
  • TI-2024-11208 Rsync: heap buffer overflow in rsync due to improper checksum length handling CVSS 3.1CRITICAL 9.8
  • TI-2026-19201 Tandoor Recipes module allows SQLite database to be externally accessible with the default settings CVSS 4.0HIGH 8.7
  • TI-2024-11209 Rsync: info leak via uninitialized stack contents CVSS 3.1HIGH 7.5
  • TI-2024-11212 Rsync: --safe-links option bypass leads to path traversal CVSS 3.1HIGH 7.5
  • TI-2024-11211 Rsync: path traversal vulnerability in rsync CVSS 3.1HIGH 7.5
See all 40 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences